We look at the division of 446787 by 90 
The aim is to understand the frequency of 90 in 446787.

Step 1:
4 divided by 90 is 0 with a remainder of 4.
Write down 0 as next digit of the result. 
Result so far: 0.0
If we take 0 away from 4, we end up with 4.
Grab the next digit (4) from the dividend, add it to 4, then carry on: 44 / 90

Going ahead to step 2:
If we divide 44 by 90, we get 0 and a remainder of 44.
Record the quotient 0 as the next digit in the result. 
Result so far: 0.0
If we take 0 away from 44, we end up with 44.
Grab the next digit (6) from the dividend, add it to 44, then carry on: 446 / 90

Step 3:
90 can be fit into 446 4 times, resulting in a remainder of 86.
The next digit of our result is 4. 
Result so far: 4.0
The remainder is 86 after subtracting 360 from 446.
Bring next digit (7) of the dividend behind the 86 and repeat the process: 867 / 90

Step 4:
90 can be fit into 867 9 times, resulting in a remainder of 57.
Put 9 as the next digit of the answer. 
Result so far: 49.0
If we take 810 away from 867, we end up with 57.
Fetch the next digit (8) from the dividend, attach it to 57 and continue: 578 / 90

Going ahead to step 5:
When dividing 578 by 90, we get 6 with a remainder of 38.
The number 6 becomes the next digit in our result. 
Result so far: 496.0
Subtract 540 from 578 to get 38.
Take the next digit (7) from the dividend and append it to 38, then repeat: 387 / 90

Going ahead to step 6:
When dividing 387 by 90, we get 4 with a remainder of 27.
Use 4 as the next digit of our solution. 
Result so far: 4964.0
Subtract 360 from 387 to get 27.
Since there are no more digits in the dividend, we add a zero to the remainder making it 270, and continue the process.

Step 7:
If we divide 270 by 90, we get 3 and a remainder of 0.
Use 3 as the next digit of our solution. 
Result so far: 4964.3
If we subtract 270 from 270, we get 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Step 8:
If we divide 0 by 90, we get 0 and a remainder of 0.
The next digit of our result is 0. 
Result so far: 4964.3
Subtracting 0 from 0 leaves us with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

Advancing to step 9:
90 goes into 0 0 times with a remainder of 0.
Use 0 as the next digit of our solution. 
Result so far: 4964.3
Deduct 0 from 0 and we're left with 0.
Since there are no more digits in the dividend, we add a zero to the remainder making it 0, and continue the process.

After the division, we end up with 4964.3 and a remainder of 0.0.